Achieving Well-Balanced Strength and Ductility in Warm-Rolled Fe–30.5Mn–8Al–1.0C Lightweight Austenitic Steels via Aging Treatment

In this study, it is attempted to achieve a balanced enhancement of strength and ductility in warm-rolled Fe–30.5Mn–8Al–1.0C (wt%) lightweight austenitic steel through aging treatment. Samples are warm rolled at 350 °C with different reductions of 25%, 45%, and 65%, followed by aging at 600 °C for 10 min. In the results, it is indicated that the 65% reduction sample exhibits an exceptional performance with well-balanced ultimate tensile strength (1610.3 ± 1.2 MPa) and total elongation (16.2% ± 0.6%). Such an excellent strength–ductility match is primarily attributed to deformation twinning, shear band refinement, and κ-carbide precipitation strengthening, which collectively contribute to an improved work-hardening capacity. In this study, the efficacy of combined warm-rolling and aging treatments in optimizing the mechanical properties of Fe–Mn–Al–C steel is highlighted.